Ventilated rib structure for gun barrels



INVENTOR I u +5 I H X Grab/'1 Jan. 16, 1962 A. Y. GRAHN VENTILATED RIBSTRUCTURE FOR GUN BARRELS Filed Jan. 5, 1961 Hrne BY W United StatesPatent 3,016,613 VENTILATED RIB STRUCTURE FOR GUN BARRELS Arne Y. Grahn,Hartford, Conn., assignor to The Poly Choke Company, Incorporated, EastHartford, Conn.,

a corporation of Connecticut Filed Jan. 5, 1961, Ser. No. 80,844 9Claims. (Cl. 33-47) This invention relates to sighting ribs for gunbarrels, and relates more particularly to a sight rib of the ventilatedtype which, while not limited thereto, is particularly well suited foremployment on a single-barrel shotgun. Sighting ribs are commonlyventilated to increase the dissipation of heat therefrom, which heat, ofcourse, is generated in the gun barrel through repeated firing of thegun and transferred from the barrel to the rib by conduction. It hasbeen found that if there is insufficient dissipation of thermal energyfrom the sighting rib, visible heat waves radiate from the rib andinterfere with the shooters sighting vision; hence, in addition toventilating sighting rib structures, it has often been found desirableto construct the rib of a material, such as aluminum, for example,characterized by high heat conduction to increase the dissipation ofheat from the rib structure. As ventilated rib structures formed of suchmaterials as aluminum, for example, cannot be welded to steel gunbarrels due to differences in the characteristics of the metals, theserib structures must be attached to steel gun barrels by mechanicalmeans, and it is known that many difiiculties have been encountered inthe past in securing these rib structures to steel barrels.

One object of the invention is to provide an improved ventilated ribstructure which is light in weight and which will not impair the balanceof the firearm to which it is attached.

Another object is to provide a ventilated rib structure characterized byimproved means for releasably securing the structure to the barrel of afirearm in such a manner that the structure is held firmly in place andmay be easily removed when desired.

Still another object is to provide a ventilated rib structurecharacterized by economical and convenient means for securing thestructure to a gun barrel.

To these and other ends, the invention resides in the novel features andcombinations to be hereinafter described and claimed.

In the accompanying drawing:

FIG. 1 is a fragmentary side elevational view of a ventilated ribstructure embodying the invention and illustrating the same inassociation with a single-barrel shotgun;

FIG. 2 is an enlarged fragmentary view further illustrating the ribstructure in side elevation, and showing the same secured to the gunbarrel;

FIG. 3 is a top plan view of the rib structure attached to the gunbarrel;

FIG. 4 is an enlarged, broken sectional view taken on line 4-4 of FIG.3; and

FIG. 5 is a sectional view taken on line 55 of FIG. 4.

In the drawing the barrel of the shotgun is indicated generally at 10,and the ventilated rib structure generally at 11. The rib structure ispreferably formed of a material characterized by high thermalconductivity to rapidly dissipate heat therefrom, a material such asalu- ICE minum, for example. If aluminum is used, it may be anodized togive the material color when color is desired. However, where it isfound desirable for one reason or another, the rib structure may beconstructed of other materials, such as suitable plastics, perhapsnylon, for example.

As best shown in FIG. 2, the rib structure is slotted, as at 12, forventilation purposes, these slots extending transversely through thestructure and being arranged at close intervals lengthwise of the barrel10. This slotting of the elongated structure provides in the structure astrip-like upper part 13 supported and spaced upwardly from a strip-likelower part 14 by integrally formed posts 15 spaced axially of thestructure at relatively long intervals. In the illustrated form, theseposts are generally of diamond shape in cross-section, having twoblunted points arranged at the respective sides of the rib structure.

As best indicated in FIG. 4, the sides 16 of each post 15 are of concaveform. Substantially midway between each post 15 and the next post 15 thelower strip 14 of the rib structure is provided with a vertical bore 17extending therethrough and having its lower end enlarged as at 18. Tosecure the rib structure to the gun barrel a plurality of threaded steelstuds 19 extend upwardly through the respective bores 17, the studshaving heads substantially recessed in the outer wall of the gun barreland secured therein as by welding.

The lower face of the strip part 14 is contoured as at 20 throughout itslength to fit closely to the gun barrel 10. The upper threaded ends ofthe studs 19 receive nuts 21 disposed between the upper and lower stripparts of the rib structure and clamping the lower strip firmly againstthe gun barrel. It will be noted from the foregoing that the studs 19are permanently secured to the gun barrel and are spaced along thelength thereof to register properly with the bores 17 provided in therib structure. In the illustrated form, the nuts 21 which receive thethreaded upper ends of the studs 19 are of a depth to substantiallyoccupy the space between the upper and lower strip parts of the ribstructure, as indicated in FIG. 2. As indicated in FIGS. 3 and 5, theupper surface of the strip part 13, which provides the sight part of therib structure, may be provided with small longitudinal grooves to lessenlight reflection from this surface, and on the upper surface of thestrip part 13 at the forward end of the rib structure a conventionalsight head 22 may be mounted.

The rib structure may be easily removed from the gun barrel forreplacement, for example, or for work on the gun barrel. A simplewrench, such as that shown in broken lines in FIG. 3 and indicated at 23may be used for this purpose. The slots in the rib structure providesuflicient clearance for the wrench for the rapid and easy removal ofthe nuts 21. The rib structure may be easily remounted by replacing thenuts in the respective slots 12 in such a manner that the nuts registerwith the respective bores 17. The nuts may be held in these positions byslightly squeezing the upper and lower strip parts of the rib structuretogether. As the nuts are dimensioned to fit closely between the upperand lower strip-like parts of the rib structure, relocation of thestructure on the gun barrel is facilitated, as the nuts 21 tend toremain in alignment with the respective bores 17 extending through thelower strip part. When the nuts are properly positioned, the ribstructure may be lowered on the studs 19 and the studs aligned with thebores 17 and the respective nuts, and when the nuts are properly seatedon the upper threaded ends of the studs the nuts may be turned with awrench until they securely clamp the rib structure to the gun barrel.

From the foregoing disclosure, it will be manifest that there isprovided an improved ventilated rib structure which may be constructedof a material characterized by high thermal conductivity to reduce ortend to eliminate heat waves radiating from the structure, and whichtend to interfere with a shooters sight vision. It will be apparent thatthe rib structure may be constructed from one of a number of materials,and in this connection it will be obvious from the foregoing that therib structure may be light in weight so as not to impair the balance ofthe gun. It will be further appreciated that the rib structure isprovided with improved means for securely fastening the rib structure tothe gun barrel. In this connection it should be noted that the fastenersare located at points remote from the posts, which space and secure theupper and lower riblike parts of the rib structure together. Also, inthis connection it should be noted that the lower strip part of the ribstructure provides a surface continuous throughout the length of thestructure for engagement with the gun barrel; in other words, a largebearing surface. Still another feature of the rib structure resides inthe provision of simple and yet effective means for releasably securingthe rib structure to the gun barrel.

While only one form of the rib structure has been illustrated in thedrawing and described above, it will be apparent to those versed in theart that the rib structure may take other forms and is susceptible ofvarious changes in details without departing from the principles of theinvention and the scope of the appended claims.

What I claim is:

1. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openings thereinwhich are relatively long and arranged at short intervals to provide anupper strip-like part separated and supported from a lower strip-likepart by a series of posts, and fastening means at points throughout thelength of the rib member and remote from said posts, said fasteningmeans including fastener elements extending through the lower strip-likepart of the rib member to secure the latter to the gun barrel.

2. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openingstherein, a first series of fastener elements on the gun barrel andspaced apart lengthwise of the latter, a second series of fastenerelements to co-act with the elements of the first series, the fastenerelements of one series extending into the rib member and into at leastcertain of said ventilating openings, and the fastener elements of oneseries having parts lying within the last-mentioned openings and beingaccessible in these openings to secure each to the correspondingfastener element of the other series to clamp the rib member to the gunbarrel.

3. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openings thereinof relatively long length, a first series of fastener elements on thegun barrel and spaced apart lengthwise of the latter, and a secondseries of fastener elements to co-act with the elements of the firstseries, the fastener elements of one series extending into the ribmember and into at least certain of said ventilating openings, and thefastener elements of one series having parts lying within thelast-mentioned openings and being accessible in these openings to secureeach to the corresponding fastener element of the other series to clampthe rib member to the gun barrel.

4. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openings thereinof relatively long length and arranged at short intervals, a firstseries of fastener elements on the gun barrel and spaced apartlengthwise of the latter, and a second series of fastener elements toco-act with the elements of the first series, the fastener elements ofone series extending into the rib member and into at least certain ofsaid ventilated openings, and the fastener elements of one series havingparts lying within the last-mentioned openings and being accessible inthese openings to secure each to the corresponding fastener element ofthe other series to clamp the rib member to the gun barrel.

5. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openings thereinof relatively long length and arranged at short intervals to provide aseries of posts spacing and supporting an upper strip-like part from alower strip-like part of the member, a first series of fastener elementson the gun barrel and spaced apart lengthwise of the latter, and asecond series of fastener elements to co-act with the fastener elementsof the first series, the fastener elements of one series extendingthrough the lower strip part of the rib member and into at least certainof said ventilating openings, and the fastener elements of one serieshaving parts lying within the last mentioned openings and beingaccessible in these openings to secure each to the correspondingfastener element of the other series to clamp the rib member to the gunbarrel.

6. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openings thereinof relatively long length and arranged at short intervals, providingposts spaced from one another along the gun barrel and separating andsupporting an upper strip part of the rib member from a lower strip partof the member, a first series of fastener elements on the gun barrel andspaced apart lengthwise of the latter, and a second series of fastenerelements to co-act with the fastener elements of the first series, eachfastener element of one series extending into one opening between twoadjacent posts substantially midway between the posts and extendingthrough the lower strip part of the rib member, and the fastenerelements of one series having parts lying within the last-mentionedopenings and being accessible in these openings to secure each to thecorresponding fastener element of the other series to clamp the ribmember to the gun barrel.

7. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openings thereinof relatively long length and arranged at short intervals to provideposts spaced along the gun barrel and separating and supporting an upperstrip part of the rib member from a lower strip part of the member, afirst series of fastener elements on the gun barrel and spaced apartlengthwise of the latter, and a second series of fastener elements toco-act with the fastener elements of the first series, the fastenerelements of one series extending into the rib member through the lowerstrip part thereof substantially midway between certain adjacent ones ofsaid posts, and the fastener elements of one series having parts lyingwithin the last-mentioned openings and being accessible in theseopenings to secure each to the corresponding fastener element of theother series to clamp the rib member to the gun barrel.

8. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openings thereinof relatively long length and arranged at short intervals along the gunbarrel, a series of upstanding threaded studs on the gun barrel in fixedrelation thereto and spaced apart lengthwise of the latter, and a seriesof nuts to co-act with the studs, the studs extending into the ribmember and into at least certain of said openings, and the nuts lyingwithin the last-mentioned openings and being accessible in theseopenings for rotary movement to secure each to the corresponding studand clamp the rib member to the gun barrel.

9. A ventilated sighting rib structure for a gun barrel, comprising arib member having means defining transverse ventilating openings thereinof relatively long length and arranged at short intervals along the gunbarrel, a series of upstanding threaded studs on the gun barrel in fixedrelation thereto and spaced apart lengthwise of the latter, and a seriesof nuts to co-act with the studs, the

studs extending into the rib member and into at least certain of saidopenings, and the nuts lying within the last mentioned openings andbeing accessible in these openings for rotary movement to secure each tothe corresponding stud and clamp the rib member to the gun barrel, theaxial dimensions of the nuts being suflicient for the nuts tosubstantially fill the width of the openings in the rib member.

No references cited.

